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DEM generation from CSK pair without having accurate height info of GCPs
Added by Tapas Dey over 6 years ago
Dear All,
If I don't have accurate height information of GCPs which need to be inserted in 'gcp_ras' step, can I not be able to generate DEM from a CSK pair?
Can I skip 'least square estimation of interferometric baseline'?
I ran 'hgt_map' with the initial baseline file generated from orbits, however, ended up getting a null *.hgt file (full black). Can anybody throw some light on this?
Regards,
Tapas
Replies (1)
DEM generation from CSK pair without having accurate height info of GCPs - Added by Charles Werner over 6 years ago
Hello Tapas,
There is always a low resolution DEM available for any area from SRTM or other
source. It is possible to improve the DEM in slant range coordinates using the
unwrapped phase of the interferometric pair and combining this with the program
dh_map_orb to calculate the sensitivity (height with respect to (w.r.t) phase).
Multiply the unwrapped phase by the scale factor in slant range geometry. Add
the height correction to the original DEM. The addition is done with the program
float_math.
This approach can be carried out iteratively, using the improved DEM to simulate
the interferogram again.
Best regards,
Charles Werner